Static building structures include many adjoining structural surfaces, such as building parapets and adjoining roof decks, which are continually subjected to ambient conditions. It is well known that movement tends to occur between such surfaces, due to such factors as abrupt changes in temperature, settling of the building structure, or for various other well known reasons.
It has been a common practice to provide such building structures with flashing or weatherproofing systems designed to channel ambient liquid (e.g. rain, snow, etc.) away from the adjoining surfaces of these structural surfaces and to also allow ventilation of moisture trapped within the confines of the adjoining surfaces. Many known flashing systems employ a flexible (generally elastomeric) sheet of material which overlies one structural member (e.g. a roof deck) and which has a portion connected to some from of adjoining planar building member (e.g. a roof parapet).
In known flashing systems it is common to provide a bracket designed to support the sheet of elastomeric material in such a manner that the sheet of elastomeric material serves to channel ambient liquids away from the areas between the adjoining surfaces. At the same time the bracket also serves to mount the elastomeric material in such a manner that ambient moisture trapped by either of the structural surfaces can be vented to the atmosphere.
Examples of various known types of flashing systems are shown in U.S. Pats. Nos. 3,132,445, 3,410,038, 3,562,971, 3,488,902, 3,444,658, 3,686,803, 3,731,439, 3,793,795, 3,246,433, and 3,365,847. Additionally, an example of a molding for mounting stretched coverings from wall ceilings can be found in disclosures such as U.S. Pat. No. 3,719,013.
It is typical of many of the known forms of flashing systems that the sheet of elastomeric material is often initially wrapped about a longitudinally extending stiffening member, and the combined stiffening member and elastomeric material are then transversely inserted into a longitudinally extending bracket part which is supported from the building parapet. This type of flashing system can be found in such disclosures as U.S. Pat. Nos. 3,562,971 and 3,410,038. Installation of such flashing systems requires care on the part of the installer to make sure that the elastomeric material is properly wrapped about the stiffening member. Otherwise the elastomeric material and stiffening member are not properly retained within the bracket. In other known types of flashing systems the elastomeric material is manually draped over a structural portion of the bracket and then a cover member is disposed in covering relationship to the elastomeric member.
Experience has shown that in either of the foregoing types of flashing systems, more time than is desirable may be spent in properly installing the system. In the event that the flashing system is improperly installed it is necessary to remove either the cover or the combined elastomeric sheet and stiffening member and reinstall the member in the bracket. Also, where the position of the elastomeric sheet is to be adjusted, the elastomeric sheet must be removed and then reinstalled.